The present invention relates to a bicycle front fork, and relates more particularly to an improved structure of fork blade for a bicycle front fork which is easy to install, and which provides a satisfactory shock absorbing function.
The fork blades of the front fork of a bicycle are commonly made in two parts, namely, the upper cylindrical casing and the lower cylindrical casing that slide one inside the other. A shock absorbing device is retained within each fork blade to absorb shocks. The shock absorbing device, as shown in FIG. 1, is a shock spring retained between an upper annular block fastened inside the upper cylindrical casing and a lower annular block fastened inside the lower cylindrical casing. The installation of the upper and lower annular blocks is complicated. Before the installation of the upper and lower annular blocks, respective holes must be made on the upper and lower cylindrical easing so that the upper and lower annular block can be respectively fastened to the upper and lower cylindrical casing through a welding process. After the process of welding, the welded area must be polished. This complicated procedure greatly increases the manufacturing cost of the front fork.
The present invention has been accomplished to provide a fork blade for a bicycle front fork which eliminates the aforesaid drawbacks. According to the preferred embodiment of the preset invention, the fork blade comprises a lower cylindrical casing, the upper cylindrical casing having a reduced bottom end inserted into the lower cylindrical casing, a forked tip member welded to the lower cylindrical casing at the bottom, a double end screw rod having a top end screwed up with locknuts to hold a buffer spring above a hollow screw member being fastened to the bottom end of the upper cylindrical casing and a bottom end connected to the forked tip member, a shock spring retained between the hollow screw member and the forked tip member, wherein the forked tip member comprises a circular upright wall welded to the inside wall of the lower cylindrical casing at the bottom and welding holes through the circular upright wall into which the melted metal for joining the forked tip member and the lower cylindrical casing fills.